单选题According to Ohm’s Law， which of the following is correct？（）A As voltage increases， resistance decreasesB As amperage decreases， resistance decreasesC As resistance decreases， amperage increasesD As resistance increases， voltage increases

题目
单选题
According to Ohm’s Law， which of the following is correct？（）
A

As voltage increases， resistance decreases

B

As amperage decreases， resistance decreases

C

As resistance decreases， amperage increases

D

As resistance increases， voltage increases

相似考题

1.The Buck(降压式变换器) is a ( ) converter.A.voltage step-upB.current step-downC.current step-upD.resistance

2.Which of the following tools is BEST used to measure voltage and amperage from a power source?()A. Loopback PlugB. MultimeterC. Power Supply TesterD. Extension Magnet

3.材料：The field current supply in older machines comes from a lower voltage direct current generator or exciter on the same shaft as the alternator. Modern machines however are either statically excited or of the high-speed brush-less type. The exciter is required to operate to counter the effects of power factor for a given load. The power factor is a measure of the phase difference between voltage and current and is expressed as the cosine of the phase angle. With a purely resistance load the voltage and the current are in phase, giving a power factor of one. The power consumed is therefore the product of voltage and current. Inductive or capacitive loads, combined with resistance loads, produce lagging or leading power factors which have a value less than one.The power consumed is therefore the product of current, voltage and power factor. The alternating current generator supplying a load has a voltage drop resulting from the load. When the load has a lagging power factor this voltage drop is considerable. Therefore the exciter, in maintaining the alternator voltage, must vary with load current and also the power factor. The speed change of the prime mover must also be taken into account.问题： The word “machines” in the passage refers to _____.A.the direct current generatorB.the alternating current generatorC.the exciterD.the prime moverWhich of the following statements is true according to the passage ?A.With a purely resistance load, the power factor is zeroB.Inductive loads combined with resistance loads produces leading power factorsC.Capacitive loads combined with resistance loads produces lagging power factorsD.With a purely resistance load, the phase angle is zeroWhen the load has a lagging power factor this voltage drop is considerable. This sentence means that _____.A.with a purely resistance load, the voltage drops too muchB.there is a considerable voltage drop in the capacitive load combined with resistance loadC.when the load is the capacitive load combined with resistance load, the voltage drops to zeroD.when the load is the inductive load combined with resistance load, the voltage drop is fairly largeThe exciter must vary with: ① load current ② the power factor, ③ speed change of the prime mover.A.①B.②C.①②D.①②③请帮忙给出每个问题的正确答案和分析，谢谢！

4.The unit of electrical resistance is theA.ampereB.voltC.wattD.ohm

更多“单选题According to Ohm’s Law， which of the following is correct？（）A As voltage increases， resistance decreasesB As amperage decreases， resistance decreasesC As resistance decreases， amperage increasesD As resistance increases， voltage increases”相关问题

  • 第1题：

    The distance between any two meridians measured along a parallel of latitude ______.

    A.increases in north latitude and decreases in south latitude

    B.decreases as DLO increases

    C.increases with increased latitude

    D.decreases with increased latitude


    正确答案：D

  • 第2题：

    With a given load on the cargo hook，the thrust on a cargo boom ______.

    A.increases as the angle to the horizontal increases

    B.increases as the angle to the horizontal decreases

    C.is greatest at an angle of 45° and decreases as the boom is raised or lowered

    D.is least at an angle of 45° and increases as the boom is raised or lowered


    正确答案：A

  • 第3题：

    As the temperature for a given mass of air increases, the ______.

    A.dew point increases

    B.dew point decreases

    C.relative humidity increases

    D.relative humidity decreases


    正确答案：D
    当一特定气团的温度上升时，相对湿度减小。

  • 第4题：

    Which of the following tools is BEST used to measure voltage and amperage from a power source?（）

    • A、Loopback Plug
    • B、Multimeter
    • C、Power Supply Tester
    • D、Extension Magnet

    正确答案:B

  • 第5题：

    According to Ohm’s Law， which of the following is correct？（）

    • A、As voltage increases， resistance decreases
    • B、As amperage decreases， resistance decreases
    • C、As resistance decreases， amperage increases
    • D、As resistance increases， voltage increases

    正确答案:C

  • 第6题：

    单选题
    For practical purposes, in a simple series circuit, the source voltage will be dropped across one resistor if it has（）.
    A

    half the resistance of the other resistor

    B

    a resistance equal to the other

    C

    at least ten times the resistance of the other

    D

    a partial short circuit


    正确答案： B
    解析： 暂无解析

  • 第7题：

    单选题
    An ammeter should be used to measure （）
    A

    the voltage between two points in a circuit

    B

    circuit continuity

    C

    current flow in a circuit

    D

    total or partial circuit resistance


    正确答案： B
    解析： 暂无解析

  • 第8题：

    单选题
    If a voltmeter is connected across a line, it must be protected with a（）
    A

    shunt

    B

    high-resistance coil in the armature circuit

    C

    low-resistance coil in the armature circuit

    D

    shunt and a coil of high resistance


    正确答案： B
    解析： 暂无解析

  • 第9题：

    单选题
    Which of the following tools is BEST used to measure voltage and amperage from a power source?（）
    A

    Loopback Plug

    B

    Multimeter

    C

    Power Supply Tester

    D

    Extension Magnet


    正确答案： C
    解析： 暂无解析

  • 第10题：

    单选题
    Which of the following statements is true concerning simple parallel resistance circuits?（）
    A

    The total current flow equals the sum of the individual currents

    B

    The total current flow equals the reciprocal of the sum of the individual currents

    C

    The total resistance equals the sum of the individual resistance

    D

    The total voltage equals the sum of the individual voltages across each resistance


    正确答案： A
    解析： 暂无解析

  • 第11题：

    单选题
    Which of the following best describes the thermodynamic effect on the pressure and volume relationship with regards to saturated gases?（）
    A

    As pressure decreases, volume increases

    B

    As volume increases, pressure increases

    C

    As volume decreases, pressure decreases

    D

    As pressure increases, volume increases


    正确答案： A
    解析： 暂无解析

  • 第12题：

    单选题
    Which of the following statements is correct concerning the viscosity of lubricating oil?（）
    A

    Viscosity will increase as temperature increases

    B

    Viscosity is a measure of a fluid s internal resistance to flow

    C

    Viscosity will decrease as temperature decreases

    D

    Viscosity is not dependent on temperature


    正确答案： C
    解析： 暂无解析

  • 第13题：

    With a given load on the cargo hook，tension in a single span topping lift ______.

    A.increases as the boom's angle to the horizontal increases

    B.is at a maximum when the boom is at a 45° angle to the horizontal

    C.increases as the boom's angle to the horizontal decreases

    D.decreases as the boom's angle to the horizontal decreases


    正确答案：C

  • 第14题：

    The error in the measurement of the altitude of a celestial body，caused by refraction，increases as the ______.

    A.horizontal parallax decreases

    B.observer's height above sea level increases

    C.humidity of the atmosphere decreases

    D.altitude of the body decreases


    正确答案：D

  • 第15题：

    Reusing frequencies in a cellular pattern (compared to “one big cell”)（）

    • A、Increases channel utilization, cost ,and interference.
    • B、Increases capacity and cost, but decreases interference.
    • C、Increases capacity, but decreases cost and interference.
    • D、Increases capacity, cost, and interference.

    正确答案:D

  • 第16题：

    Before installing a new device， a technician checks to make sure the device is on the HCL. Which of the following is the advantage of having an HCL device？（）

    • A、It is supported by other vendors
    • B、Increases performance
    • C、Decreases cost
    • D、Meets vendor standards

    正确答案:D

  • 第17题：

    单选题
    When the voltage remains constant and the resistance is increased in a series circuit, the flow of current （）
    A

    increases by the square of the original value

    B

    increases

    C

    remains the same

    D

    decreases


    正确答案： D
    解析： 暂无解析

  • 第18题：

    单选题
    Some large A-Cmotors are equipped with heatersThese could be （） (1)resistance heaters bolted directly to the frame (2)low voltage windings embedded in the motor windings
    A

    (1) only

    B

    (2) only

    C

    either (1) or (2)

    D

    neither (1) or (2)


    正确答案： C
    解析： 暂无解析

  • 第19题：

    单选题
    If the resistance of a circuit is cut in half and the applied voltage is kept constant, the current flow will be （）.
    A

    doubled

    B

    quadrupled

    C

    unchanged

    D

    cut in half


    正确答案： D
    解析： 暂无解析

  • 第20题：

    单选题
    Most conducting materials such as copper, aluminum, iron, nickel, and tungsten （）.
    A

    increase in resistance with increased temperature

    B

    increase in resistance with decreased temperature

    C

    decrease in resistance with increased temperature

    D

    increase in conductance with increased temperature


    正确答案： A
    解析： 暂无解析

  • 第21题：

    单选题
    Topside icing decreases vessel stability becauseit increases（）.
    A

    displacement

    B

    free surface

    C

    draft

    D

    KG


    正确答案： B
    解析： 暂无解析

  • 第22题：

    单选题
    According to Ohm’s Law， which of the following is correct？（）
    A

    As voltage increases， resistance decreases

    B

    As amperage decreases， resistance decreases

    C

    As resistance decreases， amperage increases

    D

    As resistance increases， voltage increases


    正确答案： C
    解析： 暂无解析

  • 第23题：

    单选题
    Which of the following statements concerning a simple parallel resistance circuit is correct?（）
    A

    The voltage drop across each resistor is the same

    B

    The total current flow equals the reciprocal of the sum of the individual currents

    C

    The total resistance equals the sum of the individual resistances

    D

    The total voltage equals the sum of the individual voltages across each resistance


    正确答案： D
    解析： 暂无解析

  • 第24题：

    单选题
    The resistance of electric wire will decrease as its （）
    A

    length increases

    B

    cross-sectional area increases

    C

    temperature increases

    D

    percent of metallic purities increases


    正确答案： A
    解析： 暂无解析

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